Reproducibility of calcium scoring of the coronary arteries: comparison between different vendors and iterative reconstructions.

backgroundThe coronary artery calcium scoring (CCS) has been widely used for cardiac risk stratification for asymptomatic patients. PURPOSE: To assess the reproducibility of CCS performed on four different computed tomography (CT) scanners, and compare the variability between two reconstruction algorithms, filtered back projection (FBP), and iterative reconstruction (IR). MATERIAL AND

methodsA CCS phantom was made from agar and contained 23 pieces of chicken bones. The phantom was repeatedly scanned using four different CT scanners: Toshiba; GE; Philips; and Siemens. Images were reconstructed using FBP and IR. Agatston and volume scores of total bone fragments were calculated and the overall differences between the instruments were evaluated using the Friedman test. Comparison of the Agatston and volume scores between the two reconstruction algorithms, for each instrument, was evaluated using the Wilcoxon signed rank test.

resultsThe difference in the Agatston scores was significantly different between the four machines (

conclusionCCS performed on different scanners varied significantly. In the Toshiba, Philips, and GE scanners, there was no significant difference in the CCS determined using either an IR or the FBP algorithm. In the Siemens scanner, applying the IR algorithm resulted in a slightly different scores, which might not be clinically significant.